Water purification system

ABSTRACT

A multi-section manifold system containing a number of replaceable filter and purification cartridges for treating the water supply of medical and dental facilities. The system operates to introduce increased concentrations of a preferred bactericide to the water immediately adjacent patient dispensing appliances. Control valving regulates and segregates flow through separate cartridges at the manifolds. A first manifold removes coarse particulates and sediment and exposes the water to an initial bactericide. A second manifold removes finer contaminants. A third concentrator manifold contains a bactericide cartridge having a percolation chamber which enhances the iodine concentration of the water in the range of 3 to 10 ppm at the patient dispensing apparatus. The percolation cartridge includes proximal and distal bactericide chambers which are, separated by an intermediate reservoir or percolation chamber.

BACKGROUND OF THE INVENTION

The present invention relates to water treatment systems and, inparticular, to a manifold system wherein a number of manifold sectionsseparately contain preferred, replaceable treatment cartridges.Associated conduits and control valving monitor and appropriatelyregulate flow through the system to provide water having an accentuatedconcentration of a preferred bactericide.

As scientists have become more aware of the many ways in which diseases,microorganisms (e.g. bacteria, parasites and viruses) and volatileorganic contaminants (VOC's) are communicated, efforts have beenextended to improve or to develop water treatment facilities to reducethe transfer of such contaminants. Many user environments which havepreviously received relatively little attention are now being studied.

An impetus of the recent attention was a widely reported case of AIDSwhich spread to patients of a dental facility. Another disease ofconcern is legionnaires disease, which is believed to be spread in highmoisture environments such as found in dental treatment facilities.

Two user environments which have been the focus of much recent attentionare dental and medical facilities. Both of these latter facilities areexposed on a daily basis to unusually large varieties of microorganismswhich can effect the health of the general population. The artificiallyhigh incidence and frequency of the exposure of either facility requiresadded precautions to properly deal with communicable diseases.

Depending upon the size of the facility, such as hospitals and largermedical and dental clinics, a limited filtration and treatmentcapability may already exist to condition the facility's general watersupply. Any available system, however, is typically concerned only withtreating the water that is received from the service utility or well toremove selected contaminants, sediments and particulates and to preventblockage of the distribution system.

The institution may also occasionally take steps to back-flush or treatthe plumbing or water distribution system to decontaminate the plumbingconduits and fixtures. These attempts are intended to decontaminate thegeneral distribution system of contaminants which have accumulated andpossibly multiplied over time, upon being admitted from the watersource. These efforts typically require shutting the system down for aperiod of time, after chemical treatments are added; allowing thechemicals time to act; and purging or back-flushing the system of thetreatment chemicals.

Although contaminants may enter a distribution system from the waterutility or well, it has been discovered that contaminants andmicroorganisms are equally likely to migrate into the system from waterdispensing fixtures in contact with the patient. Over time and with theaccumulation of the contaminants and the multiplication of the collectedmicroorganisms, the contaminants can be dispensed to subsequent users ofthe dispensing equipment.

Water fountains and patient treatment stations, such as used in dentaloffices, are particularly susceptible to the foregoing problems. Theusers of these devices are intimately exposed to transmit and receivemicroorganisms and contaminants from and to the distribution systemthrough physical contact with the dispensing equipment. The degree andduration of the contact is greater for dental stations where water isdispensed via a provided glass, which permits patient rinsing; a highpressure spray, which is dispensed from the drill; and a low pressuresprayer, which permits the dentist to direct a low volume flow forcleaning. Dental stations also exhibit a suction effect with theoperation of the drill which enhances the potential of reverse migrationof microorganisms from each patient.

Attempts have not been made to provide systems or equipment forcontinuously treating the water at such fixtures.

Appreciating the potential for bacteria, parasites and viruses tomigrate back into the conduits of the dispensing system, studies havebeen conducted at various institutions to objectively monitor thesignificance of the problem. One such study has been conducted by JanCarlsson at the Umea University, Umea, Sweden. This study has measuredsignificant initial concentrations of bacteria along with significantgrowth and regrowth of bacteria on a daily basis at a number of dentaltest stations. This study has also monitored the effects of equipmentintended to provide solutions to the problem.

Upon particularly incorporating the system of the present invention atones of such stations, appreciable reductions in the concentration ofbacteria has been demonstrated. In fact the total elimination ofbacteria has been demonstrated over a single day of use. Such studieshave further confirmed the necessity of ongoing water purificationtreatments and preferably a mechanism for controllably or continuouslydispensing bactericides and in close proximity to the dispensingequipment to assure the availability of disease and contaminant freewater.

SUMMARY OF THE INVENTION

It is accordingly a primary object of the present invention to provide asystem for treating water and liquids dispensed from equipment andfixtures exhibiting a potential for reverse migration of bacteria into awater distribution system.

It is a further object of the invention to provide apparatus compatiblewith dental and medical facilities and which may be mounted in closeproximity to patient treatment stations.

It is a further object of the invention to provide apparatus capable ofmaintaining and dispensing an increased concentration of one or morepreferred bactericides in close proximity to each treatment station.

It is a further object of the invention to provide a system which iscompatible with replaceable treatment cartridges and thereby accommodatea variety of user settings and water conditions.

It is a further object of the invention to provide a system including anumber of manifolds which separately contain cartridges designed toremove sediment, suspended particulates, microorganisms (i.e. bacteria,parasites, viruses) and VOC's from the liquid.

It is a further object of the invention to provide a system includingcontrol valving for segregating one or more of the manifolds andtreatment cartridges from the system.

It is a further object of the invention to provide at least one manifoldwhich dispenses a controlled, and predetermined relatively largeconcentration of one or more preferred bactericides into the system.

It is a still further object of the invention to provide a replaceablecartridge having proximal and distal chambers which contain amulti-valent, iodine based resin bactericide, and which chambers areseparated by an intermediate percolation reservoir or void.

Various of the foregoing objects, advantages and distinctions of theinvention are obtained in a presently preferred, multi-section manifoldsystem. The system includes a novel cartridge which contains apercolation reservoir or void intermediate proximal and distalbactericide dispensing chambers. The percolation cartridge is containedin a concentrator manifold that is mounted in close proximity to apatient treatment station. The concentrator manifold is configured toprovide relatively high concentrations of a multi-valent iodine resinbactericide to the water, particularly in the range of 3 to 10 ppm ofiodine. The enhanced levels of bactericide serves to continuouslydevitalize the intermediate distribution conduits and dispensing fixtureduring use and in-between uses. The bacteria concentration can be variedby varying the bactericide types and concentrations and the size of thepercolation reservoir. Separate and extraneous cleanings are therebyavoided.

Also provided with the system are a pair of manifolds which supportseparate cartridges for maintaining an ambient water condition inrelation to the source supply. Depending upon the condition of the watersupply, the cartridges remove suspended sediment, particulates and othercontaminants.

Associated distribution conduits, a flow meter and valving maintain apreferred water condition. A pair of two-way valves and a check valvemounted to the inlet and outlet sides of the concentrator manifoldpermit the selective coupling and decoupling of the concentratormanifold from the treatment system. Decoupling is desired where apatient may be allergic to the bactericide.

Still other objects, advantages and distinctions of the invention willbecome more apparent from the following detailed description which ispresented with respect to the appended drawings. To the extent variousmodifications and improvements have been considered, they are describedas appropriate. The invention should not be interpreted in strictlimitation to the disclosed embodiment. Rather, the invention should beinterpreted within the full scope of the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective drawing of the manifold purification system ofthe invention.

FIG. 2 is a diagrammatic drawing of the purification system shown incutaway.

FIG. 3 is a cross section drawing of the reservoir bactericide cartridgecontained in the concentrator manifold.

FIG. 4 is an exploded assembly drawing of the reservoir bactericidereservoir cartridge.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to FIG. 1, a perspective drawing is shown of a manifoldpurification system 2 of the invention. The system 2 finds particularapplication in dental and medical offices for treating and purifyingwater which is dispensed at patient treatment stations distributed aboutthe premises. Depending upon the application and the water requirementsof the station (e.g. 300 cc per patient over a twenty-five minutetreatment period), the system 2 has adequate throughput capacity toaccommodate from five to ten patient stations.

As presently constructed, the system 2 provides a purification capacitybetween cartridge replacements of 6400 liters and accommodates athroughput flow rate of 2 liters per minute, presuming the use of newcartridges. The system 2 is organized to treat water which is providedfrom a utility source that is coupled to a conduit 4 to remove suspendedsediment, particulates, contaminant microorganisms (e.g. bacteria-E.coli b, vibrio cholera, S. aureus, S. pyogenes, S. schottmulleri and L.pneumophila; parasites--giardiaasis, G. muris cysts, andcryptosporidiosis; and viruses-polio type 1, herpes simplex 2, coxsacleand echo type 2) and VOC's.

The system 2 also produces treated water at the outlet conduit 6 havingan iodine concentration in the range of 3 to 10 ppm. Such aconcentration is sufficient to purify the conduits intermediate thesystem manifolds and the patient station of typical contaminant andmicroorganism migration and growth which can occur within the conduitsand/or at the patient station.

The system 2 includes three separate manifold assemblies 8, 10 and 12,each of which contain a replaceable purification cartridge that isselected to treat the water in a preferred manner (reference FIG. 2).Each of the manifold assemblies 8, 10 and 12 is mounted to a mountingpanel 13 and includes a threaded housing 14 which depends from aheadpiece 16. Each housing 14 is secured to a headpiece 16 via matingthreads (not shown). Presently the manifolds 8, 10 and 12 are selectedto be identical, although the size and type could be varied dependingupon the requirements to properly treat the distribution system.

With attention also directed to FIG. 2, liquid is directed from an inletport 18 at each headpiece 16 to the interior of the housing 14 andthrough a contained cartridge to an outlet port 20 which is coupled tothe inlet port 18 of the adjacent manifold assembly. The inlet port 18of the manifold assembly 8 is connected to the inlet conduit 4 via anintermediate system shutoff valve 22 and conduit 23. The valve 22preferably includes a flow meter to monitor system use over time.

The outlet port 20 of the manifold 8 is coupled to the inlet port of themanifold 10 via a coupler 24. The outlet port 20 of the manifold 10 isserially coupled to the inlet port 18 of the assemblies 12 via a coupler26 and a two-way control valve 28. The outlet port 20 of the manifold 12is coupled via a conduit 30 to a check valve 31 and a second two-waycontrol valve 32 which is separately coupled to the outlet conduit 6.

With the appropriate setting of the control valves 28 and 32, thetreated liquids from the manifolds 8 and 10 can be directed to bypassthe concentrator manifold assembly 12. The ability to bypass theconcentrator manifold 12 is particularly desirable for patients who mayexhibit allergic reactions to the bactericide (i.e. a multi-valentiodine). For such patient's, the flow valve 28 is closed to prevent flowto the manifold 12, while the valve 32 is opened to convey the flow fromthe manifold 10 to the outlet conduit 6. For normal conditions, thevalve 28 is opened and the valve 32 is closed to permit serial flowthrough the concentrator manifold 12 and to the outlet conduit 6.

With continuing attention to the cross section system diagram of FIG. 2,the manifold assembly 8 includes a replaceable treatment cartridge 40.Such a cartridge is described in U.S. Pat. No. 5,126,044 and isavailable from Ecomaster Corporation of St. Paul, Minn. The cartridge 40includes a cast carbon block sediment filter 42 having a nominalporosity of 1.0 microns, which mounts about a bactericide chamber 44that projects from one end of the cartridge 40. A suitable bactericideis included in the chamber 44. The presently preferred bactericidecomprises a multi-valent, iodine based resin material which iscommercially available and further described in U.S. Pat. No. 4,238,477.

A second cast carbon filter 46 having a nominal porosity of 0.5 micronsis mounted downstream of the bactericide chamber 44 and within thecartridge housing. Admitted liquids are thus sequentially exposed to thecarbon based filters 42 and 46 with an intermediate exposure to thebactericide at the chamber 44.

The pre-conditioned water is next conducted through the manifoldassembly 10, where additional and finer contaminants are removed in acarbon bed filter. In particular, the housing 14 of the manifold 10contains a cartridge which contains a solid cast carbon block 48 havinga nominal porosity of 0.2 microns to remove and reduce any concentrationof VOC's, waterborne chemicals and other smaller contaminants.

Lastly, the pretreated water is conveyed to the concentrator manifoldassembly 12 where the bactericide concentration in the water is raisedto a concentration in the excess of 3 to 6 ppm. The increasedbactericide concentration is achieved with the use of a replaceablecartridge 50 which mounts within the housing 14. A generalized crosssection drawing of the cartridge 50 is shown at FIG. 3. FIG. 4, in turn,depicts a detailed exploded assembly drawing of the cartridge 50.

With reference to FIGS. 3 and 4, the cartridge 50 includes a cylindricalplastic housing 52 having a nominal 2.7 inch diameter and 10 inchlength. An inlet end cap 54 includes a number of ports 56 which admitliquid received from the housing 14 to the interior 58 of the housing52. A pedestal 60 projects from the center of the end cap 54 to providea cavity 62 adjacent a first screen retainer 64. A pair of back-to-backmounted screens 66, 68 are displaced from the screen 64 within thehousing a sufficient distance to contain a 50 to 100 cc's of bactericide69.

The screens 64, 66 and 68 are formed of a polypropylene material andexhibit a number of slots or through apertures to permit the passage ofthe water while retaining the bactericide. The screens 66, 68 aresecured to one another at a mating pedestal 70 and cavity 72.

The distal end of the cartridge 50 includes an end cap 74 having acenter bore 76. A porous felt washer 78 mounts to the end cap 74 andadjacent to which a second quantity of bactericide 75 is contained in asecond bactericide storage chamber. The size of the second chamber isdefined by lower screens 80 and 82. An approximate quantity of 50 to 100cc's of bactericide is contained in the distal bactericide chamber. Theend caps 54 and 74 are sonic welded to the housing 52.

A percolation reservoir or void 86 is formed between the bactericidechambers. As presently constructed, the reservoir 86 accommodates anapproximate volume of 500 cc's of liquid. This can be varied dependingupon the relative types and concentrations of bactericides at thebactericide chambers. The percolation reservoir 86 permits theaccumulation of relatively high concentrations of the bactericide withinthe contained water. This occurs since the contained water is exposed tothe bactericide of the proximal and distal bactericide chambers forrelatively long durations, depending upon the treatment flowcharacteristics. A relatively high concentration bactericide buffer isthus obtained and past which bacteria from the distribution system andpatient treatment station is not able to migrate.

As significant, the bactericide concentration is such that during normalliquid draw down and once the treatment system achieves equilibrium, thehigh concentration of bactericide, upon being admitted to the relativelyshort length of conduit to the patient station, devitalizes anyintermediate bacteria contained in the conduit or liquids. Over time anddepending upon the nominal throughput required by the patient treatmentstation, an equilibrium bactericide concentration in the range of 3 to10 ppm is preferably developed within the intermediate conduits whichdevitalizes any bacteria which may migrate or be vacuumed from thepatient station into the liquid distribution system.

The residual bactericide from the concentrator manifold 12 is thusavailable on a continuous basis, not only during patient treatments, butalso during periods of non-use to assure a safe and convenientlyavailable supply of purified water.

Although the invention has been described with respect to a presentlypreferred system organization and cartridges 40, 48 and 50, it is to beappreciated still other organizations may be suggested to those skilledin the art. Similarly, varieties of other bactericides may be containedwithin the residual cartridge 50 in lieu of the presently preferrediodine based bactericide. The following appended claims shouldaccordingly be interpreted to include all those equivalent embodimentswithin the spirit and scope thereof.

What is claimed is:
 1. A water treatment system comprising:a) aplurality of manifolds wherein each manifold includes a disposabletreatment cartridge and means for containing each cartridge within eachmanifold and directing liquid flow through each cartridge, wherein afirst of said cartridges comprises a carbon filter, a chamber containinga first bactericide and a second carbon filter, wherein a second of saidcartridges comprises a third carbon filter, wherein a third cartridgecomprises second and third chambers, which second and third chamberscontain second and third bactericides and which second and thirdchambers are separated by an intermediate open cavity space and whereinsaid second and third bactericides provide a concentration of 3 to 10ppm of bactericide to said liquid; b) means for coupling an inlet portof one of said manifolds to a water supply; c) means for seriallycoupling each of said manifolds to one another; and d) means forcoupling an outlet port of one of said manifolds to a patient treatmentstation, such that said system provides water to said patient treatmentstation having a bactericide concentration sufficient to maintaindistribution conduits intermediate said patient treatment stationessentially bacteria and contaminant free.
 2. Apparatus as set forth inclaim 1 including segregation means for selectively segregating at leastone of said manifolds from liquid flow directed through said system. 3.Apparatus as set forth in claim 2 wherein said third cartridge iscontained in a concentrator manifold which is mounted in close proximityto the patient station, and wherein said segregation means comprises afirst two-way valve coupled intermediate to an inlet port of saidconcentrator manifold, a check valve coupled to an outlet port of saidconcentrator manifold and to said patient treatment station, and asecond two-way valve coupled to an inlet side of said first two-wayvalve and an outlet side of said check valve and to said patienttreatment station.
 4. Apparatus as set forth in claim 1 wherein saidthird cartridge comprises:a) a cylindrical housing having first andsecond end caps secured to opposite ends of said housing, wherein oneend cap includes an inlet port and the other includes an outlet port; b)a plurality of porous means mounted within said housing to define aplurality of seriatim chambers, wherein a first chamber defined adjacentthe inlet port includes the second bactericide, wherein a second chambercomprises a cavity space, and wherein a third chamber defined adjacentthe outlet port includes the third bactericide.
 5. Apparatus as setforth in claim 4 wherein said bactericide comprises a multi-valentiodine resin.
 6. Apparatus as set forth in claim 5 wherein a pluralityof screen members mate with one another to separate each of said secondand third bactericides from said cavity space.
 7. A water treatmentsystem comprising:a) a plurality of manifolds wherein each manifoldincludes a disposable water treatment cartridge and means for containingeach cartridge within each manifold and directing liquid flow througheach cartridge, wherein a concentrator one of said cartridges comprisesfirst and second chambers which contain first and second bactericidesand which first and second chambers are separated by an intermediateopen cavity, and wherein said first and second bactericides provide aconcentration of 3 to 10 ppm of bactericide to said liquid; b) means forcoupling an inlet port of one of said manifolds to a water supply; c)means for coupling each of said manifold means in flow communicationwith one another; and d) means for coupling an outlet port of said oneof said manifolds in close proximity to a patient treatment station suchthat said system provides water to said patient treatment station havinga bactericide concentration sufficient to maintain distribution conduitsintermediate said patient treatment station essentially bacteria andcontaminant free.
 8. Apparatus as set forth in claim 7 wherein saidconcentrator cartridge comprises:a) a cylindrical housing having firstand second end caps secured to opposite ends of said housing, whereinone end cap includes an inlet port and the other includes an outletport; b) a plurality of porous screens mounted within said housing todefine a plurality of seriatim chambers, wherein a first chamber definedadjacent the inlet port includes said first bactericide, wherein asecond chamber comprises a cavity space and wherein a third chamberdefined adjacent the outlet port includes said second bactericide, andwherein at least one of said first and second bactericides comprises amulti-valent iodine resin.
 9. Apparatus as set forth in claim 8 whereinsaid first and second bactericides each comprise a multi-valent iodineresin.
 10. Apparatus as set forth in claim 9 wherein said first andsecond bactericides comprise equal quantities of said multi-valentiodine resin.